<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<% 
String rand = (String)session.getAttribute("rand"); 
String input = request.getParameter("rand"); 
if(rand.equals(input)){ 
out.print("<script>alert('验证通过！');</script>"); 
} else{ 
out.print("<script>alert('请输入正确的验证码！');location.href='login.jsp';</script>"); 
} 
%> 
</body>
</html>